We need to make start parameter of Blob.slice optional, per the latest File API spec: http://dev.w3.org/2006/webapi/FileAPI/#dfn-Blob
Created attachment 91339 [details] Proposed Patch
There was a gigantic thread about this on webkit-dev. I'm surprised more of those players aren't cc'd here.
Jian: Could you please CC the relevant people and get this resolved? it's been in the queue for almost a month.
Per the discussion, we decide to do no change to how code generator handles optional parameter since it is the right behavior as in ECMA-262. The spec author Arun also updated the File API spec to explicitly illustrate the case for optional end parameter. The only change in this patch to make start parameter as optional. It does not change any other existing behaviors. CC peoples that were in the discussion if they have more to day.
Comment on attachment 91339 [details] Proposed Patch Looks fine.
Committed as https://trac.webkit.org/changeset/87181.